Development and optimization of a novel pin-loaded CFRP strap: A hybrid experimental-numerical approach

Self-anchored carbon fiber reinforced polymer (CFRP) strap cables eliminate bulky metallic anchorages, yet stress concentrations within the curved anchorage zone continue to limit their load-carrying efficiency. This study integrates experimental testing, finite element (FE) simulations, and analytical modeling, aiming to address this limitation through strap geometry optimization and interfacial behavior characterization. Static tensile tests were first performed on straps with wedge angles of 27°, 29°, and 33°. The results showed that reducing the wedge angle significantly improves load capacity, with the 27° strap achieving the highest average fracture stress above 2000 MPa. These experiments were then used to validate a three-dimensional FE model, which subsequently enabled a systematic parametric analysis across wedge angles, strap layers, and interface friction coefficients. The FE-generated database was employed to evaluate the predictive accuracy of an existing orthotropic thick-walled ring formulation. By introducing a correction factor that explicitly accounts for wedge angle and interfacial friction, the model was extended to reproduce load capacities with an error less than 3 % and to capture clear parametric trends. This modified closed-form formulation provides the first friction-sensitive design tool for CFRP straps, offering practical guidance for efficient lightweight cable systems in long-span structures. • A lightweight self-anchored CFRP strap system eliminates bulky metallic anchorages. • Experiments and FE simulations reveal wedge-angle-dependent fracture mechanisms. • Parametric analyses define an optimal design window for stable strap efficiency. • A friction-sensitive analytical model achieves FEM-level accuracy within ±3 %. • The closed-form model enables rapid, reliable design of long-span CFRP cable systems.